Improvement in screens for dry-gas purifiers



UNITED STATES PATENT OEEToE.

EDWARD DUFFEE, OF HAVERHILL, MASSACHUSETTS.

IMPROVEMENT IN SGREENS FOR DRY-GAS PURIFIERS.

Specification forming part of Letters Patent N o. 58,393, dated October 2, 1866.

To all whom 'it may concern:

Be it known that I, EDWARD DUFFEE, of Haverhill, in the county ot' Essex and State of Massachusetts, have invented au Improved Screen for Dry Goal-Gas Purifiers; and I do hereby declare that the following, taken in connection with the drawings which accompany and form part of this specification, is a description ot' my invention sufficient to enable those Skilled in the art to practice it.

Letters Patent No. 56,490 were granted July 17, 1866, upon an improved screen for dry coal-gas purifiers made by me. Said invention consisted in constructing screens for dry coalgas puritiers of strips of thin Wood crossing each other, and either riveted together orinterlaced inthe form ot' basket-work, supported by a framework of metal, or its equivalent.7

My presentinvention relates to an improvement upon such construction made by me, which construction is defective in that when the llingis made of interlaced and continuous strips the projection ot' such strips beyond the edges ot the frames prevents the adjacent edgesof the respective frames making up each horizontal screen from closely abutting, and causing a weakening and breaking of thestrips from abrasion.

My present invention is designed to remedy this defect, and consists in grooving the outer edges of each frame, so that Where the strips pass along such edges they shall be sunk below the general surface of such edge, this construction permitting the adjacent frames to abut closely together and against the inner side of the purifier, and preventing abrasion and wear ofthe interlacing strips.

rI/lhe drawings represent, respectively, a horizontal section and an edge view of one ot' the frames.

a denotes the outer bars.; b, the cross-bars c, the long thin strips of wood, passed continu ously through holes bored through the bars, and crossed and interlaced, as will be readily understood.

The outer edge of each bar a is grooved out, as seen at d, to a width corresponding to or a little in excess of the width of the interlacingstrips, and to a depth suflicent to allow the strip to be sunk below the general surface of the edge of the bar, as seen in the drawings.

I claim- In a screen for dry coal-gas purifiers made up of crossed or-interlaced thin strips of wood supported by a frame-work, grooving the outeI edges of each frame so thatthe strips shall be embedded in or sunk below the surface of each outer edge, to prevent abrasion and to allow the frames to abut closely together, substantially as set forth. u

`EDWARD DUFFEE. Witnessesz' GEORGE STEVENS, A. B. JAQUEs. 

